Intermittent selective rotary printing apparatus



y 1959 w. RITZERFELD ETAL 2,896,534

INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 1 Gerhard RH'zevFelA July 28, 1959 w. RITZERFELD ETAL v INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet S a 3% m @w S Im m M MI- 1, U M

July 28,1959

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INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 4 M! M2 M3 M4 9 4 Inventory W k l R'wrceu A y 1959 w. RITZERFELD ETAL 2,896,534

INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 5 Inventors Br qcpl g y.

y 1959 w. RITZERFELD ETAL 2,896,534

INTERMITTENT- SELECTIVE ROTARY PRIK QTIN G APPARATUS y 1959 WARITZERFELD ETAL 2,896,534

1 INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet "7 EIE 3W1 l l l HJT.T.T...I..

y 1959 w. RITZERFELD ET AL 2,896,534

INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 8 Inverzaar wllktlm Rff'zgrk Qerhard RH'uv-RH.

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INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 9 y 1959 w. RITZERFELD ETAL INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets- Sheet 10 ,v 1959 w. RITZERFELD ET AL 2,396,534

INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24, 1957 12 Sheets-Sheet 11 Fig /5 July 28, 1959 w. RITZERFELD ETAL 2,896,534

INTERMITTENT SELECTIVE ROTARY PRINTING APPARATUS Filed April 24. 1957 12 Sheets-Sheet 12 .[m errfors Wilhelm PilzerFdJ and Ger/lard RH- Q IJL Mama,

United States Patent Ofiice 2,896,534 Patented July 28, 1959 7 SELECTIVE ROTARY PRINTING The present invention refers to printing and duplicating machines, and more particularly to the rotary type in which the printing or duplicating is done by means of a printing form attached to a rotatable printing roll.

The invention has particular significance for rotary printing apparatus of the type set forth and having a counter rollerfor pressing the copy sheet or. the like against the printing form by means of an electrical moving device which in turn is controlled by certain control means. In the case of selective intermittent printing the control means are suitable for selecting any desired line or section or combination of lines or sections for the reproduction from the printing form.

It is one object of this invention to; provide for a printing. apparatus of the type set forth which can be operated at a higher speed than heretofore known which means the possibility of producing more copies per hour.

For the same reason, another object of this invention is the provision of elements of such a printing apparatus which themselves individually and jointly can be operated at a higher speed than heretofore known.

Still another object of the invention is the provision of a printing apparatus of the type set forth in which the amount of pressure exerted by said counter roll on the copy sheet can be adjusted to the requirements most generally depending upon the thickness of the copy material.

It is still another object of this invention to provide means which permit an adjustment of the spacing between the individual lines or sections printed on the copy sheet in such a manner that this spacing is equal to, or smaller or larger than the spacing of the corresponding lines or sections on the printing form.

It is still another object of this invention to provide for a printing apparatus of the type set forth which can be used when desired as well for intermittent or selective printing as for continuous printing of the entire content of the printing form.

Another object of this invention is the provision of a printing apparatus of the type set forth in which the control means used for the selection of the lines or sections of the printing form is capable of being used in such a manner that with one control means a preselected group of different lines or sections of the printing form can be selected for the reproduction.

With above objects in view, a preferred embodiment of this invention comprises within a printing apparatus, in combination, a frame, a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto, a counter roll carried by the frame for movement to and from an operating position in close proximity to the printing roll for the purpose of pressing a copy sheet against said printing form, said counter roll having an axis parallel to that of the printing roll; the apparatus further includes an electrical moving device operatively connected to said counter roll for moving the same to and from said operating position, wherein this electrical device includes at least one electromagnet; the apparatus further includes means for applying electrical impulses of different intensity to said electromagnet.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 is a lateral view of a rotary printing apparatus having a plurality of electromagnets forcontrolling the counter roll, the left side wall of the apparatus being omitted;

Fig. 2 is a top view, partially sectional, of the rotary printing apparatus according to Fig. 1;

Fig. 3 is a wiring diagram for the operation of the printing apparatus according to Figs. '1 and 2;

Fig. 4 is an alternative wiring diagram applicable to the same printing apparatus according to Figs. 1 and 2;

Fig. 5 is a side view of a modified embodiment of the invention showing a printing apparatus for selective intermittent printing, the left side wall of the machine being omitted;

Fig.- 6 is a fractional view of a printing form from which selected sections or lines are intended to be reproduced;

Figs. 7, 8 and 9 illustrate three different forms with printed lines into which selected lines or sections of the printing form are to be imprinted by the apparatus according to the invention; i

Fig. 10 is a wiring diagram for a printing apparatus according to Fig. 5 showing means for controlling the reproduction of preselected groups of lines from a printing form;

Fig. 11 is another wiring diagram showingthe electrical circuits of a printing apparatus according to the invention;

Fig. 12 is a front view of a part of a control arrangement according to Fig. 11;

Fig. 13 is a cross section of the device shown by Fig. 12, the section being taken along line CD;

Fig. 14 is the side view of another modified form of a printing apparatus according to the invention, including means for adjusting the line spacing in the reproduction, the left side wall of the apparatus being omitted;

Fig. 15 is a wiring and circuit diagram for a printing apparatus according to this invention, the counter roll being electronically controlled and including a variable transformer for adjusting the line spacing; and

Fig. 16 is another wiring diagram for a modified form of the apparatus according to Fig. 15, including voltage regulator means and means for adjusting the voltage of the voltage regulator means.

The embodiment of the invention illustrated by Figs. 1-4 is a rotary printing apparatus with a printing roll 1 and a movable counter roll 10 which can be moved out of the inoperative position shown in Fig. 1 into an operative position in close proximity with the printing roll 1 for pressing a copy sheet 21 against the form 2 attached to the printing roll 1. The counter roll "10 is moved by an electrical moving device which according to the present invention includes a plurality of electromagnets Ml-M8. It has been found that by using not one single electromagnet in said moving device for the counter roll 10, but by providing a plurality of electromagnets working conjointly the size of the individual electromagnets of such a group can be considerably smaller than that of a single magnet that would furnish the same power as the entire group of small magnets. The advantage of a greater number of small magnets consists in the possibility of operating the printing apparatus at a considerably higher speed than in the other case because the smaller magnets respond considerably faster to an electric impulse than a large magnet.

It is to be borne in mind that the speed at which the printing roll'1 can be rotated for the purpose of reproduction depends greatly upon the time required for the counter roll to move from inoperative position into operative position and, after the engagement between the two' rollers,.upon the time required by the counter roll 10 to move back from operative position into inoperative position; This is of particular importance in the case of intermittent printing where the counter roll 10 has to be moved into operative position every time one line or section of the printing form is to be transferred to the copy sheet 21 which may add up to a great number of strokes of the counter roll 10 during one cycle of reproduction.

In the example of the printing apparatus illustrated by Figs. 1 and 2 the magnets M1-M8 are stationarily mounted on the machine frame. The armature 260 of the magnets Ml-M8 are each connected by forked pieces 261 and links 262 to a pull bar 263. Eachpull bar 263 in turn operates a system of toggle levers 16 and 17 joined by a pivot pin 18 to which the bar 263 is attached. The toggle part 16 is pivotally mounted on an eccenter pin 15. The counter roll 10 is rotatably mounted in a pair of levers 25 pivoting around an axle or shaft 26. On the other hand, the counter roll 10 is also supported by the toggle part 17 so that whenever the bar 263 is pulled to the left, as seen in Fig. 1, the toggle system is operated in such a manner that the counter roll 10 is forced against the printing roll 1 and if a copy sheet or the like 21 is fed by the feed rollers 22, 23 into the printing area between the two rolls, a reproduction of a section or line of the form is effected on the copy sheet passing between the two rolls. When the energization of the magnets Ml-M8 is discontinued the spring 273 returns the moving parts of the moving device for the counter roll 10 and the latter back into their inoperative position.

For the purpose of selective printing the selection of lines or sections of the pritining form that are to be reproduced is done by means of a control panel 230 which includes a number of actuating members or push buttons operating a corresponding number of control elements or switches which in Figs. 3 and 4 are indicated as T1-T10.

The magnets Ml-MS are connected with the control elements T1'T10 as shown for example in Fig. 3. By selectively actuating the push buttons or actuating elements T1-T10 of the control panel 230 the circuits for the selected lines or sections that are to be reproduced are prepared. Each of the switches controlled by the actuating members T1-T10 includes two sets of contacts. The one is in circuit with the electromagnets M1-M10, while the other set of contacts belongs to a separate circuit for operating signal lights Ll-Lltl simultaneously so that these lights indicate which selection has been made. The electric energy for the lamp circuit is furnished by a transformer 264 connected to a supply line of alternating current which transforms the line voltage to a low voltage so that the signal lamps Ll-Lltl can be kept as small as possible.

The circuit illustrated in Fig. 3 includes impulse generating means which in this case consist of a set of stationary contacts Kl-KIO, each being associated with one of the actuating elements Tll-Tlll and therefore also associated with corresponding lines or sections of the printing form 2. During the operation of the apparatus a movable contact element 265 passes along the support 266 of the contacts Kl-Kltl so as to successively close the circuits to the magnets Ml-MS provided that the particular circuit has been prepared by operation of corresponding actuating elements T1Tl. Consequently, whenev'er'the, movable contact 265 passes one of the stationary contacts Kl-Kltl the electromagnets M1-M8 will be energized whenever asection or line of the print- 1ng form is in printing position for which the associated actuating element T1 etc. has been preset before the start of the printing operation.

An example of an impulse generating device of the type mentioned above is further illustrated in Fig. 11 where the stationary contacts K1 etc. are arranged along a circular line, while the movable contact 265 is essen tially an arm rotatable around the center of that circular line which at the same time is in this case the center of the support member 266.

According to Figs. 3, 4 and 11 the electromagnets Ml-MS are supplied with direct current from a rectifier 267. For accelerating the response of the magnets a parallel circuit 268 consisting of a resistance and a capacitor is interposed between the rectifier 267 and the magnets.

There are cases when it is not desirable to preselect individual lines or sections of the printing form 2 for selective reproduction. It may be desired to reproduce in the printing process all the lines and sections of the printing form in consecutive order. For this mode of operation of the apparatus a special switch or control member T11 is provided as shown in Fig. 3. The switch T11 has two separate contacts, one of which is in the circuit between the rectifier 267 and the magnets M1-M8 while the. other set of contacts belongs to a lamp circuit leading to the special signal lamp L11 which is to indicate when the printing apparatus is set for reproduction of the whole content of the printing form. It is evident that the device as illustrated by Fig. 3 can be used alternatively either for selective intermittent printing by use of the control panel 230, or for continuous reproduction of the entire printing form by operation of the special switch T11.

Fig. 4 illustrates a modified embodiment of the device illustrated by Fig; 3. In this case the magnets M1- M8 are divided into two groups, one designated a and including the magnets M1 M4, the other group being designated b and including the magnets M5-M8. The selection and preparation of circuits is done in this case in the same manner as described with respect to Fig. 3. However, in the impulse generating device, each pair of consecutive contacts as for instance K1 and K2; K3 and K4; K5 and K6, etc. are connected to one line which leads to the magnets, however the two groups of magnets are alternatingly connected to alternating pairs of the above-mentioned contacts. For instance contact K1 or K2 would operate the magnet group a while the contacts K3 or K4 would operate the magnet group 12. Therefore, during a cycle of operation of the apparatus, and depending upon the selection made by actuating the selector means, in the average the two groups of magnets. will operate alternatingly which makes the operation more efficient and more economical.

For intermittent and selective printing where speed in response of the magnet is of great importance, it is advisable to apply to the electromagnets a voltage substantially higher than the rated voltage of these individual magnets. There is no harm expected to be done to the magnets because the duration of energization is very short in intermittent printing. On the other hand, the speed of response of the magnets at such a raised voltage is greatly increased. It has been found that it is advantageous to raise the voltage applied to the magnets to at least twice their rated voltage.

It is evident that'the group of magnets working conjointly like Ml-M4 have to furnish all the power which is required to press the counter roll 10 against the copy sheet or the like '21 and to press the latter against the printing form 2 carried by the printing roll 1. In practical operation of a printing apparatus according to the invention it is frequently desirable that the pressure applied by the counter roll 10 be adjusted, for instance if the paper of the copy sheet is thinner or stronger which requires different amounts of pressure for a good reprodilation, In order to change the total pressure applied by the counter roll, according to Fig. 4 individual magnets of each group can be switched off and rendered ineffective by means of the manually operated switches 270. The operation of the switch 270 in each case can be used also to close a circuit parallel with the associated magnet and including a resistor 269. In this manner by switching off one or more magnets of a group and by switching on instead one or more of the resistors 269 the pressure ap plied by the counter roll can be modified within a wide range.

The circuit means shown in Fig. 4 also includes a special control member which is to be used when instead of selected intermittent printing a reproduction of the whole content of the printing form 2 is desired. The control switch 278 has several sets of contacts, two of which serve for supplying the electrical energy to the magnet groups a and b when the switch is closed, while another normally open contact is in circuit with a special signal lamp L11 as described above, and a fourth set of contacts which is normally closed is in circuit with the selector means so that when the switch 271 is operated this latter contact is opened and the whole selector means and impulse generating device is rendered ineffective while the circuits to the magnets are closed. It is to be noted that in the circuit between the rectifier 267, switch 278 and magnets Ml-M8 a resistor 272 is connected. As mentioned above it is contemplated to operate the magnets at a voltage higher than the rated voltage. However when the apparatus is used for continuous printing by operation of switch 271, then for the protection of the magnets the voltage has to be reduced to substantially their rated voltage because in this case they will stay energized during an appreciable period of time.

On account of the above-described arrangement the apparatus can be used when desired for selective and intermittent printing or alternatively for continuous printmg.

It should be noted that the above-described means for moving the counter roll 10 between an inoperative position and an operative position can be used in a quite similar manner also for controlling or for producing the similar movements of other elements of a printing apparatus as for instance a moistening device or an inking device containing rollers that have to be moved between operative and inoperative positions.

A modified embodiment of the invention is illustrated by Figs. 510. The general arrangement is similar to that of Fig. 1. The printing roll 1 is driven from a motor, not shown, via belt 8 and a gear train 32, 33, 34 and a one-turn clutch, not shown. The counter roll 10 is operated by electromagnets M1-M8 through toggle levers 16, 17, arms '25 and push bar 35. The electromagnets M1M8 are electrically controlled from a control panel 36 and by means of a rotary switch 266.

The embodiment illustrated here is specifically designed for reproduction of selected sections or lines of a printing form 2 in such a manner that the selection can be made in advance for certain groups of sections and lines. Fig. 6 illustrates a printing form 2 with 36 lines and shows in what manner a printing program. may be laid out for instance to reproduce on a preprinted business form F1 as shown in Fig. 7 a sequence of sections or lines A, B, C of Fig. 6. Or, for instance, on a business form F2 a se quence of sections and lines D, E, F, G, may be printed as shown in Fig. 8. Further still another group of sections and lines H, J, K, may be printed on a business form F3 as shown by Fig. 9. It is evident that in every one of these different operations, all made from the same original printing form 2, different selections have to be made in the apparatus before the printing operation. With selector means as illustrated by Figs. 3, 4 and 11, it would i be necessary, for instance in the case of the example Fig.

7, to individually prepare the operation by operating singly and individually all the selector elements T2-T8, T18 and T21.

In accordance with the invention however the opera tion can be greatly simplified. It happens very frequently that certain business forms like the ones illustrated in Figs. 79 are used again and again in the course of operation. Therefore the certain sections of such a business form into which data or information have to be imprinted, remain always the same. Therefore, it is of great advantage to be able to preset the printing apparatus according to the invention for certain groupings of sections and lines so that whenever a particular business form is to be imprinted with information only one selector or control member has to be operated.

As shown by Fig. 10, in this embodiment the selector means includes a number of actuator elements T1-T5, each associated with a selected group of control elements being individual sets of switch contacts. The individual control elements of each group are connected on one side with appropriate groups of magnets M5-M8 and on the other side with associated members of the impulse generating device. In this case the impulse generating device comprises a stationary support 266 carrying a series of contact members Kll-K36 arranged alternatingly in two circular rows concentric with the center of support 266 which is also the center of rotation of a movable contact arm 265 having two contact points adapted to travel along a circular path identical withthe circular lines along which the contacts K1-K36 are arranged.

If for insance the business form P1 of Fig. 7 is to be imprinted with the sections A, line B, and line C of the printing form 2, then in this case only the one single actuating means T1 has to be operated so that the series or group of contacts corresponding to all the lines of the sections A, B and C are selected and the appropriate circuits correspondingly prepared. When then during the operation and during the rotation of the printing roll 1 the contact arm 265 rotates synchronously with the printing form, the various contacts Kl-K36 are connected into the circuits butonly those contacts which are associated with the control elements operated by the actuator element T1 will close at the appropriate moment the circuit for the energization of one or the other group of magnets Ml-MS. It can be seen that in a similar manner the actuator element T2 operates control elements which correspond to the sections and lines illustrated in Fig. 8, while the next section of the selector means including the actuator element T3 would serve to operate the control elements for producing the imprint on the business form shown by Fig. 9.

The diagram of Fig. 10 also shows that the selector means include also contacts in a lamp circuit which is indicated by Roman Figures I-lV so that for instance in the case of the selector elements operated by actuator element T1 the signal lamps L2-L8, L18 and L21 would be switched on simultaneously with the preparation of the circuit for the corresponding contacts of the impulse generator device 265, 266. It will be understood from Fig. 10 that whenever a' program for imprinting certain business forms is to be changed, it is only necessary to change the wiring so as to connect certaincontacts Kl-K36 with different ones of the control elements or switches actuated by one particular actuator element T1-T5.

Figs. 11, 12 and 13 illustrate a modified form of the apparatus according to the invention in which also a certain printing program can be prepared in such a manner that whenever certain selections are needed repeatedly like in the case of imprinting standardized business forms, then certain control means can be operated so that a preselected group of'selector or control elements of the selector means are simultaneously moved into operative position by operation of one single actuator element.

Preselection of groups of selector means or elements can be done in a purely mechanical way as shown specifically in Figs. 12 and 13. 37 designates the frame or .top of the general control panel 230 in Fig. 1 or 36 in :Fig. 5; Each of the actuator members or buttons T1Tll7 is provided with an extension arm 33 inside the frame 37. In an adjacent portion of the frame 37 a number of special actuator members 41 and 42 are mounted so that they can be moved against the action of their respective springs 44, guided by slot and screw engagement 43, in such a mannerthat an extension 39 or 40, respectively, engages the extension arm 38 of certain actuating members Tl, etc. It is evident that the extensions 39 and ttl, respectively, can be formed at their ends in such a manner that a preselected number of the extension 33 of various actuating members T1 are engaged when the actuators 41 or 42 are operated. Fig. 12, for instance, shows that the extension 39 is cut so that upon operation of the actuator 41 the actuatingelements "Fl-T4 and T7 would be actuated, while by operation of the actuator 42 the actuating elements T4, T5, T9 and T10 would be operated.

It should be noted that by the mechanical arrangement illustrated in Figs. 12 and 13, the operability of the regular actuators T1 etc. is not impaired by the provision of the separate group actuator members 41, 42, so that the whole selector device can be used at will either for selecting individual lines by means of the individual selector members T1 etc. or by selecting preselected groups by means of the group selectors 4i and 42.

It hardly needs any explanation that, of course, for

different business forms or for other printing programs the extensions 39 or 40 must be provided with different cutouts to suit the requirements.

It may be added here, that in the embodiment illustrated in the diagram Fig. 10 the whole set of group actuator means as shown there may be incorporated in sepa rate attachments or separate control panels which can be removed from the printing apparatus and reconnected at will by temporary connections like plugs and sockets to the standard control panel. A number of different such prepared and preconnected separate group control panels can be used interchangeably in connection with one standard control panel or by all means with one standard printing apparatus according to the invention.

It has been found that for various reasons the spacing of the individual consecutive lines appearing on the printed copy sheet 21 is not always and necessarily the same as that existing between the consecutive lines Z1, Z2 etc. on the printing form 2. In some cases a variation in the line spacing between the printed sheet and the printing form may be due to variations in thickness or stiffness of the material of the copy sheet 21;. In any case, particularly when imprints have to be produced on existing business forms with predetermined line spacing as i lustrated in Figs. 7, 8 and 9, an incorrect line spacing on the printed sheet as compared with the printing form is highly undesirable. On the other hand there may be cases where a possibility of producing a printed sheet with a'line spacing different from that existing on the printing form would be highly desirable.

It has been found, that it is possible to control the line spacing on the printed sheet to some extent by varying or adjusting accordingly the intensity of the elec trical impulse injected into the magnets which operate the counter roll ltl. It must be realized that the line spacing appearing on the printed copy sheet 21 greatly depends upon the time required for the counter roll 10 to move from its inoperative position into its operative position and back from the operative position into the inoperative position. This time element depends upon the space existing between the counter roll 10 and the printing roll 1. in its inoperative position and upon the speed with which the counter roll 1.0 is -moved toward the printing roll 1 under a particular impulse. It is clear that the speed of this last-mentioned movement increases in accordance with the intensity of the electrical impulse. Examination of these conditions lead to the rule that by increasing the intensity of the impulse the line spacing appearing on the printed sheet is increased to amounts larger than the line spacing on the printed form, while reducing the intensity of the impulse leads to-narrower spacing of the lines on the printed sheet 21.

In order to adjust and control the line spacing under all circumstances an embodiment of the invention as shown in Fig. 14 includes a variable resistor 47 which can be controlled from the outside of the apparatus and which is connected in the direct current circuit between the rectifier and the magnets M1M8. By varying the resistance of the resistor 47 the voltage applied to the magnets is correspondingly altered and thereby likewise the intensity of the electrical impulse controlling the movement of the counter roll 10 is adjusted so as to obtain the desired line spacing on the copy sheet 21.

In Figs. 5, 10 and 14 impulse generating means have been shown consisting of a stationary member 266 supporting a series of contacts K1 etc. which are arranged along two circular arcs concentric tothe center of the srpport 266 which is also the center of rotation of a contact arm 265 carrying two contacts 46 which during the rotation travel along a path substantially identical with the abovementioned circular arcs along which the contacts are located. It can be seen from the abovementioned figures that in a preferred embodiment of this apparatus the contacts K1, K2 etc. are divided into two groups one group containing the contacts associated with every second line or section of the printing form while the second series contains the contacts associated with the other sections or lines of the printing form. Therefore as the two contacts 46 during the rotation pass over the two series of stationary contacts K1, K2 etc. the circuit for the magnets is alternatingly closed by the engagement of one of the contacts 46 with a contact of the one "series of contacts and a contact of the other series of contacts. For example as the arm 265 moves first the contact K1 would be engaged, then K2, then K3, then K4, etc. It will be further noted from inspection of the Figs. 5, 10 and 14, that the contacts of the two separate series are respectively offset against each other in the direction of the travel of the contacts 46 in such a manner that the engagement of one of the contacts 46 with any contact of one series is not terminated before the other contact 46 engages the next following contact of the other series of contacts. Therefore, if consecutive lines or sections of the printing form have been selected for reproduction as for instance line Z1 and Z2, then as the contacts 46 travel over the stationary contacts no interruption of the flow of current through the corresponding magnet occurs between the engagement of thecontacts K1 and K2. The action of the impulse generator regarding these two consecutive contacts overlaps. Therefore the whole mechanism. has not to go into inoperative position after the printing of the line Z1 but may stay in operative position until the printing of the line 22 is completed. Consequently, whenever consecutive lines out of the printing form are reproduced unnecessary strokes of the moving device for the counter roll '10 and of the latter are saved which causes the apparatus to work more quietly and also tends to make it possible to run the whole machine at a higher speed without causing other difiiculties.

Referring now to Figs. 15 and 16, an apparatus according to the present invention can be equipped with electronic means for operating the electromagnets and for transmitting electrical impulses to them. The general arrangement of the electronic circuit shown in Figs. 15 and 16 corresponds to that which we have dis- 9 closed and described in our previous U.S. patent application Serial No. 622,496. For the purpose of changing or adjusting the intensity of the electrical impulse the arrangement according to Fig. 15 includes a variable transformer 47 which is interposed between the supply of electric energy in form of alternating current and the input transformer which feeds the rectifier tubes 48, 49. It is evident that by changing the input voltage.

by means of the device 47 the intensity of the direct current put through the magnets Mil-M8 can be changed accordingly for all the purposes described above with respect to the previous embodiments of this invention.

According to Fig. 16, the electronic arrangement is modified so as to include voltage regulator devices so that the apparatus being sensitive to voltage controlling the intensity of the electrical impulses transmitted to the magnets, can operate exactly as desired even if the line voltage from the outside should be subjected to fluctuations or changes. The voltage regulation mainly consists of tubes 50, 51 and transformers 52, 53. The rectifier tubes 50, 51 are fed with alternating current by the transformer 52, the resulting direct current being fed through filters 54 to the magnets M1M8. An amplifier tube 57 is controlled via a filter 55 and a voltage regulator tube 56. A reference voltage controlled by the voltage regulator tube 56 is applied to the amplifier tube 57, the reference voltage being adjustable by a potentiometer 58 to any desired figure. In case there occurs a change or fluctuation of voltage in the outside line as introduced to the transformer 52, then the inductivity of the control chokes 59 is affected so as to cause a certain phase shift. Thereby the rectifier tubes 50 and 51 are controlled through an impulse transformer 60 and as a result the direct current voltage delivered by the rectifiers is kept constant to a value which is controlled and adjusted by the potentiometer 58.

Therefore by operating the potentiometer 58 the intensity of the electrical impulse applied to the electromagnets in the operation of the device can be predetermined.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of printing apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in printing apparatus for intermittent and selective printing, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended Within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electro-magnet responding at different speeds to electrical impulses of different intensity; generator means for gencrating electrical impulses sequentially during rotation of said printing roll and for applying said impulses to said electro-magnet and including selective control means for coordinating the application of said impulses with selected sections of said printing form when said selected sections are in printing position opposite said counterroll; means for applying a voltage to said generator means; and means for adjusting the intensity of said impulses.

2. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively'connected to said counter-roll for moving the same to and from said operating position, said device including at least one electro-magnet responding at different speeds to electrical impulses of difierentintensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

3. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of difierent intensity; generator means for generating electrical impulses sequentially during rotation of said printing roll and for applying said impulses to said electromagnet and including selective control means for coordinating the application of said impulses with selected sections of said printing form when said selected sections are in printing position opposite said counter-roll; means for applying a voltage to said generator means; and means for adjusting said voltage so as to change the intensity of said impulses.

4. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counterroll having an axis parallel to said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; generator means for generating electrical impulses sequentially during rotation of said printing roll and for applying said impulses to said electromagnet and including selective control means for coordinating the application of said impulses with selected sections of said printing form when said selected sections are in printing position opposite said counter-roll; means for applying a voltage to said generator means; and means including a variable resistance in circuit with said electromagnet for adjusting said voltage so as to change the intensity of said impulses.

5. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form; said counterroll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; generator means for generating electrical impulses sequentially during rotation of said printing roll and for applying said impulses to said electromagnet and including selective control means for coordinating the application of said-impulses with selected sections of said printing form when said selected sections are in printing position opposite said counter-roll; means for applying a voltage to said generator means; and means including a variable transformer in circuit with said means for applying a voltage for adjusting said voltage so as to change the intensity of said impulses.

6. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting said voltage so as to change the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members. of said impulse generating de vice in operative condition; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

7. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving-the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition; means connected in said circuit for rendering said impulse gencrating device and said selector means ineffective when desired and for applying to said electromagnet a voltage substantially lower than said voltage applied to said impulse generating device, so that during a revolution of said printing roll all sections of said printing form are consecutively printed while said counter-roll is held by said electromagnet under the action of said lower voltage in operating position during the printing of all sec tions of said printing form; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

8. in a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counterroll carried by said frame for movement between an in operative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counterroll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying to said impulse generating device a voltage substantially higher than the rated voltage of said electromagnet for generating a high intensity impulse and for causing a high-speed response of said electromagnet to such impulses; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

9. In a printing apparatus as set forth in claim 8, an arrangement, wherein said means for applying a voltage to said impulse generating device are capable of applying a voltage at least twice the rated voltage of said electromagnet.

10. In a printing apparatus for intermittentv selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet respondsaid impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition; independent means connected in said circuit for applying to said electromagnet a voltage substantially lower than said voltage applied to said impulse generating device so that said printing apparatus can be used alternatively for intermittent and selective printing by operation of said selector means and said impulse generating device or, when desired, for continuous printing, by operation 'ofsaid independent means, whereby during a revolution of said printing roll all sections of said printing form are consecutively printed while said counter-roll is held by said electromagnet under the action of said lower voltage in operating position during the printing of all sections of said printing form; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

11. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counterroll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including a plurality of electromagnets connected in parallel for joint operation and each responding at different speeds to electrical imnumber of jointly operating electromagnets left operative; an electrical impulse generating device for applying impulses to said electromagnets; means for applying a volt age to said impulse generating device; and meansfor adjusting the intensity of said impulse.

14. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame \for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical pulses of different intensity; generator means for genr erating electrical impulses sequentially during rotation of said printing roll and for applying said impulses to said electromagnets and including selective control means for coordinating the application of said impulses with selected sections of said printing form when said selected sections are in printing position opposite said counterroll; means for applying a voltage to said generator means; and means for adjusting the intensity of said impulses.

12. In a printing apparatus as set forth in claim 11, an arrangement wherein said plurality of electromagnets is divided into at least two groups each comprising a plurality of said electromagnets, and wherein means are provided for selectively applying said impulses to a selected group of said electromagnets.

13. In a printing apparatus, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement to and from an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including a plurality of electromagnets connected in par allel for joint operation and each responding at different speeds to electrical impulses of different intensity; means for selectively rendering at least one of said electromagnets inoperative for adjusting the pressure of said counter-roll against said copy sheet depending upon the impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition, said selector means including at least one actuating member associated with a selected group of said control elements for actuatingthe latter so that a corresponding group of said members of said impulse generating device are placed in operative condition when said actuating member is operated; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

15. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one: electromagnet responding at ditferent speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form, said set of members being divided into two series of members, the members associated with consecutive sections of said printing form being located alternatingly in one of said series, and including an element movable along said two series of members for alternatingly engaging during its movement members of one and the other of said two series thereof, respectively, said members being off-set in the direction of said movement to such a degree that during said movement the engagement between said movable element and one member of one of said series is not terminated before said movable element engages the following member of the other one of said series; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into saidcircuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associ- 'so that a corresponding group of said members of said impulse generating device are placed in operative condition when said actuating member is operated; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

16. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of said printing roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of diiferent intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form, said selector means including at least one actuating member associated with a preselected plurality of said control elements and movable between an inoperative and an operative position, said actuating member having means for engaging said preselected plurality of control elements when it is moved into operative position so that said control elements can be actuated either individually or as a group; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing from and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition, said selector means including at least one actuating member associated with a selected group of said control elements for actuating the latter so that a corresponding group of said members of said impulse generating device are placed in operative condition when said actuating member is operated; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same.

17. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form, said counter-roll having an axis parallel to that of saidprinting roll; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position, said device including at least one electromagnet responding at different speeds to electrical impulses of different intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing forms; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting the intensity of said electrical impulse; selector means mounted on said frame and including a set of contact means re spectively associated with sections of said printing form and with said members of said impulse generating device, and movable between a circuit-opening and a circuitclosing position, a set of actuating elements respectively associated with said contact means and movable between an inoperative position and an operative position in which said contact means are moved into circuit-closing position by said associated actuating elements, and at least one group of actuator means associated with a preselected plurality of said actuating elements and movable between an inoperative and an operative position in which said preselected plurality of said actuating elements is moved into operative position, so that said contact means can be operated either individually or as a group; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same. 7 18. In a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form and for thereby moving said copy sheet through the area of engagement between said printing roll and said counter-roll, said counter-roll having an axis parallel to that of said printing roll, said counter-roll in inoperative position being spaced from said printing roll a preselected distance so that the time required to move said counter-roll into said operating position after said printing roll during its rotation has reached a certain position and said movement of said counter-roll has been started, depends upon the speed of said movement and upon said distance; an electrical moving device operatively connected to said counter-roll for moving the same to and from said operating position at said pnedetermined speed, said device including at least one electromagnet responding at different speeds 'to electrical impulses of dilferent intensity; an electrical impulse generating device comprising a set of members respectively associated with sections of said printing form; circuit means connecting said impulse generating device with said electromagnet for actuating the same whenever an electrical impulse is generated by said impulse generating device, and including means for applying a voltage to said impulse generating device; means connected into said circuit for adjusting said voltage so as to change the intensity of said electrical impulse; selector means mounted on said frame and including a set of control elements respectively associated with sections of said printing form and with said members of said impulse generating device for placing selected members of said impulse generating device in operative condition; and drive means operatively connected with said printing roll and with said impulse generating device for moving the same whereby selected sections of said printing form are printed in a sequence of sections spaced from each other at intervals predetermined by said preselected distance and by the speed of movement of said counter-roll into operating position depending upon the respective adjustment of said voltage.

19. a printing apparatus for intermittent selective printing, in combination, a frame; a printing roll carried for rotation about its axis by said frame and adapted to have a printing form fixed thereto; a counter-roll carried by said frame for movement between an inoperative position and an operating position in close proximity to said printing roll for pressing a copy sheet against said printing form and for thereby moving said copy sheet through the area of engagement between said printing roll and said counter-roll, said counter-roll having an axis parallel to that of said printing roll, said counter-roll in inoperative position being spaced from said printing roll a preselected distance so that the time required to move said counter-roll into said operating 

